Specific aims: Aim 1. Collect skin tumors (approximately 40 squamous cell (SCC) and basal cell (BCC) carcinomas (approximately 40 each) and malignant melanomas (MM)(approximately 20). Skin tags will be collected from sun exposed (approximately 50) and non exposed (approximately 25) skin of adults. Aim 2. We will select a panel of 15 tumor suppressor genes involved in growth cycle regulation, apoptosis, cell adhesion, differentiation, tissue invasion and metastasis and which are known to be down regulated in many tumor types by aberrant gene methylation of promoter regions. We will determine the methylation profile of our tumor and skin samples. Aim 3. We will compare and contrast the methylation patterns of the major forms of skin cancer and between sun exposed and non exposed skin samples.